Life-History Strategies and the Effectiveness of Sexual Selection

Oikos ◽  
1992 ◽  
Vol 63 (2) ◽  
pp. 318 ◽  
Author(s):  
Kirk O. Winemiller
Keyword(s):  
Sexual Selection ◽  
Life History ◽  
Life History Strategies

scholarly journals Sex-specific predation risk and the evolution of sexual dimorphism in immunocompetence: a theoretical analysis

2014 ◽  
Author(s):  
Benjamin Fanson ◽  
Eirik Søvik
Keyword(s):  
Sexual Selection ◽  
Life History ◽  
Sexual Dimorphism ◽  
Immune Function ◽  
Predation Risk ◽  
Reproductive Effort ◽  
Life History Strategies ◽  
Defense Strategies ◽  
Differential Predation ◽  
Predation Costs

Sexual dimorphism in immunocompetence, with males having lower immune function, is a prevalent pattern in nature. The main evolutionary explanation for this pattern is that males preferentially allocate resources away from immune function and towards reproductive effort to increase their competitiveness for limited females. However, the role of differential predation risk between the sexes has not been considered, despite predation risk being a major driver of life history strategies and male sexual traits often having associated predation costs. It is unclear whether increased predation risk should increase or decrease investment in immune function, as males have been shown to utilize both behavioural (e.g. decrease foraging activity) and/or life-history (e.g. decrease investment in sexual trait) defense strategies to manage predation risk. Here, we modelled optimal resource acquisition and allocation towards immune function under differential predation risk with multiple defense strategies. If males have limited defense strategies, increasing predation risk caused males to trade-off immune function for reproductive effort, leading to reduced immunocompetence. In contrast, if males can only decrease predation risk through reduction of reproductive effort (e.g. decrease colouration or calling rates), then increasing predation risk causes immune function to increase. If males can utilize multiple defense strategies and sexual selection is low, then males maintain a constant immune function as predation risk increases. Sexual selection robustly resulted in decreased immunocompetence. Overall, our results suggest that predation plays an important role in the evolution of sexual dimorphism in immunocompetence, but predicting its effect requires understanding the integrated defense strategies available.

scholarly journals Sex-specific predation risk and the evolution of sexual dimorphism in immunocompetence: a theoretical analysis

2014 ◽  
Author(s):  
Benjamin Fanson ◽  
Eirik Søvik
Keyword(s):  
Sexual Selection ◽  
Life History ◽  
Sexual Dimorphism ◽  
Immune Function ◽  
Predation Risk ◽  
Reproductive Effort ◽  
Life History Strategies ◽  
Defense Strategies ◽  
Differential Predation ◽  
Predation Costs

Sexual dimorphism in immunocompetence, with males having lower immune function, is a prevalent pattern in nature. The main evolutionary explanation for this pattern is that males preferentially allocate resources away from immune function and towards reproductive effort to increase their competitiveness for limited females. However, the role of differential predation risk between the sexes has not been considered, despite predation risk being a major driver of life history strategies and male sexual traits often having associated predation costs. It is unclear whether increased predation risk should increase or decrease investment in immune function, as males have been shown to utilize both behavioural (e.g. decrease foraging activity) and/or life-history (e.g. decrease investment in sexual trait) defense strategies to manage predation risk. Here, we modelled optimal resource acquisition and allocation towards immune function under differential predation risk with multiple defense strategies. If males have limited defense strategies, increasing predation risk caused males to trade-off immune function for reproductive effort, leading to reduced immunocompetence. In contrast, if males can only decrease predation risk through reduction of reproductive effort (e.g. decrease colouration or calling rates), then increasing predation risk causes immune function to increase. If males can utilize multiple defense strategies and sexual selection is low, then males maintain a constant immune function as predation risk increases. Sexual selection robustly resulted in decreased immunocompetence. Overall, our results suggest that predation plays an important role in the evolution of sexual dimorphism in immunocompetence, but predicting its effect requires understanding the integrated defense strategies available.

scholarly journals Natural variation in plant telomere length is associated with flowering time

2021 ◽  
Author(s):  
Jae Young Choi ◽  
Liliia R Abdulkina ◽  
Jun Yin ◽  
Inna B Chastukhina ◽  
John T Lovell ◽  
...  
Keyword(s):  
Life History ◽  
Telomere Length ◽  
Flowering Time ◽  
Dna Sequences ◽  
Genome Wide Association Study ◽  
Genomic Analysis ◽  
Life History Strategies ◽  
Length Variation ◽  
Chromosomal Structure ◽  
Chromosome Integrity

Abstract Telomeres are highly repetitive DNA sequences found at the ends of chromosomes that protect the chromosomes from deterioration during cell division. Here, using whole genome re-sequencing and terminal restriction fragment assays, we found substantial natural intraspecific variation in telomere length in Arabidopsis thaliana, rice (Oryza sativa), and maize (Zea mays). Genome-wide association study (GWAS) mapping in A. thaliana identified 13 regions with GWAS-significant associations underlying telomere length variation, including a region that harbors the telomerase reverse transcriptase (TERT) gene. Population genomic analysis provided evidence for a selective sweep at the TERT region associated with longer telomeres. We found that telomere length is negatively correlated with flowering time variation not only in A. thaliana, but also in maize and rice, indicating a link between life history traits and chromosome integrity. Our results point to several possible reasons for this correlation, including the possibility that longer telomeres may be more adaptive in plants that have faster developmental rates (and therefore flower earlier). Our work suggests that chromosomal structure itself might be an adaptive trait associated with plant life history strategies.

Intraspecific hybridization, life history strategies and potential invasion success in a parasitoid wasp

2012 ◽  
Vol 26 (6) ◽  
pp. 1311-1329 ◽  
Author(s):  
Chiara Benvenuto ◽  
Sandrine Cheyppe-Buchmann ◽  
Gérald Bermond ◽  
Nicolas Ris ◽  
Xavier Fauvergue
Keyword(s):  
Life History ◽  
Parasitoid Wasp ◽  
Invasion Success ◽  
Life History Strategies ◽  
Intraspecific Hybridization

scholarly journals High Genetic Variance in Life-History Strategies within Invasive Populations by Way of Multiple Introductions

2008 ◽  
Vol 18 (5) ◽  
pp. 363-367 ◽  
Author(s):  
Benoît Facon ◽  
Jean-Pierre Pointier ◽  
Philippe Jarne ◽  
Violette Sarda ◽  
Patrice David
Keyword(s):  
Life History ◽  
Genetic Variance ◽  
Life History Strategies ◽  
Multiple Introductions

Demography of Xenosaurus platyceps (Squamata: Xenosauridae): a comparison between tropical and temperate populations

2008 ◽  
Vol 29 (2) ◽  
pp. 245-256 ◽  
Author(s):  
Carissa Jones ◽  
Isaac Rojas-González ◽  
Julio Lemos-Espinal ◽  
Jaime Zúñiga-Vega
Keyword(s):  
Life History ◽  
Population Growth ◽  
Adult Mortality ◽  
Life History Strategies ◽  
Relative Importance ◽  
Theoretical Frameworks ◽  
Population Growth Rates ◽  
Relative Contribution ◽  
Two Populations ◽  
Average Fitness

Abstract There appears to be variation in life-history strategies even between populations of the same species. For ectothermic organisms such as lizards, it has been predicted that demographic and life-history traits should differ consistently between temperate and tropical populations. This study compares the demographic strategies of a temperate and a tropical population of the lizard Xenosaurus platyceps. Population growth rates in both types of environments indicated populations in numerical equilibrium. Of the two populations, we found that the temperate population experiences lower adult mortality. The relative importance (estimated as the relative contribution to population growth rate) of permanence and of the adult/reproductive size classes is higher in the temperate population. In contrast, the relative importance for average fitness of fecundity and growth is higher in the tropical population. These results are consistent with the theoretical frameworks about life-historical differences among tropical and temperate lizard populations.

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